we have a problem on the CBM we can't open the project( error reading sourceblock) but the other projects are open

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Most likely the problem will go away by resetting FSD client or server used by this ES.

Client reset is easy; Close CBM, kill the AfwFSDNode.exe service in the client; wipe the \OperateITTemp\FsdCache folder, then start CBM and attempt to open the project.

To circle a defective FSD server, disable that particular FSD service provider or shut down or disconnect the entire server from the network, then try opening the CBM project.

This may single out a bad FSD server. Stop the FSD service provider or perform "Maintenance Stop". Then rename the \OperateITData\FsdServer folder and relight the service again (or reboot). After cold synchronization has completed, try opening the project again.